1. Field of the Invention
The present invention relates to a microplasma source and, more particularly, to a microplasma source and a sterilization system suitable for the sterilization of reusable medical apparatus and furthermore for injured or infected tissues inactivation/sterilization.
2. Description of Related Art
When reusable medical apparatus such as surgical or dental medical devices are sterilized, total elimination of all microorganisms such as bacteria, fungi, or viruses from the apparatus has to be confirmed to prevent any possible infection to a next patient. However, currently known sterilization methods such as dry autoclave process, the treatment of chemical bactericide such as ethylene oxide, and physical irradiation will result in different degrees of degradation or damage to the treated surfaces. Therefore, medical facilities commence to adopt low temperature and pressure plasma sterilization. In this kind of plasma sterilization, the electrical energy stimulates extremely excited gas in vacuum and produce ionized particles, meta-stable species, and free radicals which can interact with bacteria and therefore cause damage to microorganism metabolism below 50° C. This method is harmless to the environment (main byproducts are CO2 and H2O) and thus can be used to treat thermolabile and wet-labile medical apparatus.
In order to avoid potential damage to the sterilized medical devices and reduce the operation cost of the in-vacuum low temperature plasma apparatus, non-thermal and normal pressure dielectric barrier discharge (DBD) plasma is currently developed for sterilization. The DBD plasma is produced between two parallel plate electrodes of which one is covered with a dielectric material to avoid undesirable generation of electric arcs. Unfavorable influences caused by high energy applied to generate plasma can be reduced or avoided in the DBD plasma. Highly reactive species to be used for the sterilization of the medical devices can be afforded in the DBD plasma with low energy consumption. Nevertheless, there are limits in the use of the above mentioned DBD plasma because most medical apparatus have irregular shapes, and it is difficult for the DBD plasma to cover all exposed surfaces of the medical apparatus or to act on the bacteria hidden in some apertures thereof. Hence, the sterilization performance of the DBD plasma is limited by the shapes of the medical devices to be treated. In addition, the residual bacteria which escape sterilization are generally found hiding in a wet condition such as an aqueous solution. Thus, the applied method has to ensure complete sterilization of the medical devices containing the aqueous solution. However, if the DBD plasma is used to sterilize the medical devices containing an aqueous solution, the difficulty of ensuing complete sterilization will increase considerably.
Hence, if a microplasma technique is developed to achieve complete sterilization of the medical devices containing an aqueous solution and the technique can be flexibly applied to various appearances or shapes of different samples, the sterilization time and the cost of purchasing related devices can be dramatically decreased, so as to facilitate the development of related fields using this technique.